[Population biology of cestode genus Triaenophorus in natural and man-made water bodies].

A comparative study of the frequencies of occurrence and distribution of the abundances of pike parasites, tapeworms of the genus Triaenophorus, was carried out in natural lakes and water bodies contaminated by the Kostomuksha mining and concentration mill (Northern Karelia). We demonstrate that the wide presence of T. crassus and T. nodulosus in natural northern lakes is due to the diversity of aquatic organisms and the structure of trophic relations. The abundance of both species is modeled by the negative binomial distribution. Relations in the host-parasite system are stable. Estimates of the parameter k of the negative binomial distribution reflect the changes in the interactions in the host-parasite system. T. nodulosus has survived in the man-made water body storing the highly mineralized recirculated water from the mill. Disturbance-related distinctions were detected in the parameters of the T. nodulosus abundance distribution in the host population. In the Okunevoye Lake, where the water discharged from the tailings dump is more diluted, the infection rates in pike did not differ from those in undisturbed water bodies.